Lens, light emitting device and method of manufacturing the lens and the light emitting device

ABSTRACT

A lens includes a cover part and a light-shielding part. The cover part includes a lens part, a connection part extending downward from lateral sides of the lens part, and one or more flange parts each extending outward from a lower-end portion of the connection part. The lens part and the connection part define a recess having an opening facing downward. The flange parts extend outward from a periphery of the opening of the recess. The lens part, the flange parts, and the connection part are formed of a thermosetting first resin and continuous to one another. The light-shielding part covers outer lateral surface of the connection part and is formed of a thermosetting second resin having a greater light-absorptance or a greater light-reflectance than the thermosetting first resin. The flange parts have a greater thickness than the connection part.

CROSS-REFERENCE TO RELATED PATENT APPLICATION

The present application claims priority under 35 U. S. C. § 119 toJapanese Patent Application No. 2018-162680, filed Aug. 31, 2018. Thecontents of Japanese Patent Application No 2018-162680 are incorporatedherein by reference in its entirety.

BACKGROUND OF THE INVENTION Field of the Invention

The present disclosure relates to a lens and a light emitting device,and a method of manufacturing the lens and the light emitting device.

Discussion of the Background

Applications for flush light sources used in cellular phones and othermobile devices, a light emitting device may include an LED elementmounted on a circuit board, a cover having an optical lens disposedfacing the LED element, and a light-reflecting member integrally formedwith the cover, for example, described in Japanese patent publicationNo. 5139915. In the light emitting device described in Japanese patentpublication No. 5139915, a metal film is used as the light-reflectingmember and the metal film is formed by way of, for example, vacuum vapordeposition.

SUMMARY OF THE INVENTION

A lens according to one embodiment of the present disclosure includes acover part and a light-shielding part. The cover part includes: a lenspart having one or more lateral sides; a connection part constitutingone or more lateral side walls each extending downward from a respectiveone of the one or more lateral sides of the lens part; and one or moreflange parts each extending outward from a lower-end portion of acorresponding one of the one or more lateral side walls. The lens partand the connection part define a recess having an opening facingdownward. The lens part defines a bottom surface of the recess. The oneor more lateral side walls define lateral surfaces of the recess, whichdefine the opening of the recess. The one or more flange parts extendoutward from a periphery of the opening of the recess. The lens part,the one or more flange parts, and the connection part are formed of athermosetting first resin and continuous to one another. Thelight-shielding part covers outer lateral surfaces of the one or morelateral side walls and are formed of a thermosetting second resin havinga greater light-absorptance or a greater light-reflectance than thethermosetting first resin. The flange part has a greater thickness thanthe connection part.

A lens according to one embodiment of the present disclosure includes acover part and a light-shielding part. The cover part includes: a lenspart having one or more lateral sides; a connection part constitutingone or more lateral side walls each extending downward from a respectiveone of the one or more lateral sides of the lens part; and one or moreflange parts each extending outward from a lower-end portion of acorresponding one of the one or more lateral side walls. The lens part,the one or more flange parts, and the connection part are formed of athermosetting first resin and are continuous to one another. The one ormore flange parts each have a thickness greater than 30 μm. Thelight-shielding part covers outer lateral surfaces of the one or morelateral side walls and is formed of a thermosetting second resin havinga greater light-absorptance or a greater light-reflectance than thethermosetting first resin.

A light emitting device according to one embodiment of the presentdisclosure includes a light emitting element and a lens. The lensincludes a cover part and a light-shielding part. The cover partincludes: a lens part having one or more lateral sides; a connectionpart constituting one or more lateral side walls each extending downwardfrom a respective one of the one or more lateral sides of the lens part;and one or more flange parts each extending outward from a lower-endportion of a corresponding one of the one or more lateral side walls.The lens part and the connection part define a recess having an openingfacing downward. The lens part defines a bottom surface of the recess.The one or more lateral side walls define lateral surfaces of therecess, which define the opening of the recess. The one or more flangeparts extend outward from a periphery of the opening of the recess. Thelens part, the one or more flange parts, and the connection part areformed of a thermosetting first resin and are continuous to one another.The light-shielding part covers outer lateral surfaces of the one ormore lateral side walls and is formed of a thermosetting second resinhaving a greater light-absorptance or a greater light-reflectance thanthe thermosetting first resin. The one or more flange parts have agreater thickness than the connection part. The lens part is disposed ata location allowing light from the light emitting element to betransmitted through the lens part.

A light emitting device according to one embodiment of the presentdisclosure includes a light emitting element and a lens. The lensincludes a cover part and a light-shielding part. The cover partincludes: a lens part having one or more lateral sides; a connectionpart constituting one or more lateral side walls each extending from arespective one of the one or more lateral sides of the lens part; andone or more flange parts each extending outward from a lower-end portionof a corresponding one of the one or more lateral side walls. The lenspart, the one or more flange parts, and the connection part are formedof a thermosetting first resin and are continuous to one another, with athickness of each of the one or more flange parts being greater than 30μm. The light-shielding part covers outer lateral surfaces of the one ormore lateral side walls and is formed of a thermosetting second resinhaving a greater light-absorptance or a greater light-reflectance thanthe thermosetting first resin. The lens part is disposed at a locationallowing light from the light emitting element to be transmitted throughthe lens part.

A method of manufacturing a lens according to one embodiment of thepresent disclosure includes: forming a cover blank, the forming a coverblank including, injecting a thermosetting first resin in a first moldand curing the first resin, to form a cover blank having a plurality ofcover parts, each of the cover parts including a lens part having one ormore lateral sides, a connection part constituting one or more lateralside walls each extending downward from a respective one of the one ormore lateral sides of the lens part, and one or more flange parts eachextending outward form a lower-end portion of a corresponding one of theone or more lateral side walls, the lens part, the flange part, and theconnection part being continuous to one another, the lens part and theconnection part defining a recess having an opening facing downward, theone or more flange parts extending outward from a periphery of theopening of the recess; removing a part or all parts of the first mold;arranging the cover blank in a second mold; forming a lens blank, theforming a lens blank including, injecting a thermosetting second resinhaving a greater light absorptance or a greater light reflectance thanthe thermosetting first resin into the second mold, and curing thethermosetting second resin, to form a lens blank having alight-shielding part between adjacent ones of the cover parts; andobtaining individual lenses, the obtaining individual lenses including,taking out the lens blank from the second mold, and cutting the lensblank at the light-shielding part located between adjacent ones of thecover parts to obtain individual lenses each with outer surfaces of theone or more lateral side walls (and an upper surface of each of the oneor more flange parts) covered by the light-shielding part.

A method of manufacturing a lens according to one embodiment of thepresent disclosure includes: forming a cover blank, removing a part oran entire of the first mold, arranging the cover blank in a second mold,forming a lens blank, and obtaining individual lenses. The forming acover blank includes injecting a thermosetting first resin in a firstmold and curing the first resin to form a cover blank having a pluralityof cover parts, each of the cover parts including a lens part having oneor more lateral sides, a connection part constituting one or morelateral side walls each extending downward from a respective one of theone or more lateral sides of the lens part, and one or more flange partseach extending outward form a lower-end portion of a corresponding oneof the one or more lateral side walls. The lens part, the flange part,and the connection part being continuous to one another. The one or moreflange parts have a thickness greater than a thickness of the connectionpart. The lens part and the connection part define a recess having anopening facing downward. The lens part defines a bottom surface of therecess. The one or more lateral side walls constituted by the connectionpart define lateral surface(s) of the recess, which define the openingof the recess. The recess is located inward of the one or more flangeparts. The removing a part or an entire of the first mold is performedafter the cover blank is formed. In the arranging the cover mold in asecond mold, the cover blank is arranged in a second mold. The forming alens blank includes injecting a thermosetting second resin in the secondmold, the second resin having a greater light absorptance or a greaterlight reflectance than the thermosetting first resin, and curing thesecond resin to form a light-shielding part between adjacent ones of thecover parts. The obtaining individual lenses includes taking out thelens blank from the second mold and cutting the lens blank at thelight-shielding part located between the adjacent ones of the coverparts to obtain individual lenses each having the outer lateral sides ofthe connection part (and an upper surface of each of the one or moreflange parts) covered by the light-shielding part.

A method of manufacturing a lens according to one embodiment of thepresent disclosure includes: forming a cover blank, the forming a coverblank including, injecting a thermosetting first resin in a first mold,and curing the first resin, to form a cover blank having a plurality ofcover parts, each of the cover parts including a lens part having one ormore lateral sides, a connection part constituting one or more lateralside walls each extending downward from a respective one of the one ormore lateral sides of the lens part, and one or more flange parts eachextending outward from a lower-end portion of a corresponding one of theone or more lateral side walls, the lens part, the one or more flangeparts, and the connection part being continuous to one another, the oneor more flange parts having a thickness greater than 30 μm; removing apart or all parts of the first mold; arranging the cover blank in asecond mold; forming a lens blank, the forming a lens blank including,injecting a thermosetting second resin having a greater lightabsorptance or a greater light reflectance than the thermosetting firstresin into the second mold and curing the thermosetting second resin, toform a lens blank having a light-shielding part between adjacent ones ofthe cover parts; and obtaining individual lenses, the obtainingindividual lenses including, taking out the lens blank from the secondmold, and cutting the lens blank at the light-shielding part locatedbetween the adjacent ones of the cover parts to obtain individual lenseseach with outer surfaces of the one or more lateral side walls (and anupper surface of each of the one or more flange parts) covered by thelight-shielding part.

A method of manufacturing a lens according to one embodiment of thepresent disclosure includes forming a cover blank, the forming a coverblank including, injecting a thermosetting first resin in a first mold,and curing the thermosetting first resin, to form a cover blank having aplurality of cover parts, each of the cover parts including a lens parthaving one or more lateral sides, a connection part constituting one ormore lateral side walls each extending downward from a respective one ofthe one or more lateral sides of the lens part, and one or more flangeparts each extending from a lower-end portion of a corresponding one ofthe one or more lateral side walls, each of the one or more flange partshaving a greater thickness than the connection part, and the lens part,the one or more flange parts, and the connection part being continuousto one another; removing the first mold; cutting the cover blank at theflange part located between adjacent ones of the cover parts; arrangingthe cut cover blank in a second mold; forming a lens blank, the formingthe lens blank including, injecting a thermosetting second resin havinga greater light absorptance or a greater light reflectance than thethermosetting first resin into the second mold and curing thethermosetting second resin to form a lens blank having a light-shieldingpart located between adjacent ones of the cover parts; and obtainingindividual lenses, the obtaining individual lenses including, taking outthe lens blank from the second mold, cutting the lens blank at thelight-shielding part located between the adjacent ones of the coverparts to obtain individual lenses each with outer surfaces of the one ormore side walls and an outer end surface, in addition to an uppersurface, of each of the one or more flange parts covered by thelight-shielding part.

A method of manufacturing a light emitting device according to oneembodiment of the present disclosure includes providing a lens accordingone of the methods described above, and arranging the lens such thatlight from the light emitting element is transmitted through the lenspart of the lens.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 is a perspective sectional view schematically showing a structureof a light emitting device that includes a lens according to a firstembodiment, taken along a line passing through the center of the lightemitting device;

FIG. 2 is a plan view schematically showing a structure of a lensaccording to the first embodiment;

FIG. 3 is a cross-sectional view, taken along line III-III of FIG. 2 ,schematically showing a structure of a lens according to the firstembodiment, in which the line is passing through the center of the lens

FIG. 4 is a cross-sectional view schematically showing a structure of alight emitting device according to the first embodiment, taken along aline passing through the center of the light emitting device;

FIG. 5 is a flow chart showing a procedure of a method of manufacturinga lens according to the first embodiment;

FIG. 6A is a cross-sectional view schematically illustrating forming acover blank in a method of manufacturing a lens according to the firstembodiment;

FIG. 6B is a cross-sectional view schematically showing removing a firstmold in a method of manufacturing a lens according to the firstembodiment;

FIG. 6C is a cross-sectional view schematically illustrating arranging acover blank in a second mold and forming a lens blank in a method ofmanufacturing a lens according to the first embodiment;

FIG. 6D is a cross-sectional view schematically illustrating cutting thelens blank to obtain individual lenses in a method of manufacturing alens according to the first embodiment;

FIG. 7A is a cross-sectional diagram illustrating a state of arranging alens according to the first embodiment via an engaging member withrespect to a substrate having a light emitting element mounted thereon;

FIG. 7B is a cross-sectional diagram illustrating a state of engaging aflange part of a lens according to the first embodiment with an engagingmember;

FIG. 7C is a cross-sectional view illustrating a state the lensaccording to the first embodiment disposed on the substrate, with theflange part of the lens engaged with the engaging member;

FIG. 8A is a cross-sectional view schematically showing a structure of alight emitting device that includes a lens according to a secondembodiment, taken along a line passing through the center of the lightemitting device;

FIG. 8B is a cross-sectional view schematically illustrating arranging acover blank in a second mold to form a lens blank in a method ofmanufacturing a lens according to the second embodiment;

FIG. 8C is a cross-sectional view schematically illustrating cutting thelens blank to obtain individual lenses in a method of manufacturing alens according to the second embodiment;

FIG. 9 is a cross-sectional view schematically showing a structure of alight emitting device that includes a lens according to a thirdembodiment, taken along a line passing through the center of the lightemitting device;

FIG. 10 is a flow chart showing a procedure of a method of manufacturinga lens according to the third embodiment;

FIG. 11A is a cross-sectional view schematically illustrating forming acover blank in a method of manufacturing a lens according to the thirdembodiment;

FIG. 11B is a cross-sectional view schematically illustrating cutting acover blank in a method of manufacturing a lens according to the thirdembodiment;

FIG. 11C is a cross-sectional view schematically illustrating arranginga cut cover blank in a second mold and forming a lens blank in a methodof manufacturing a lens according to the third embodiment;

FIG. 11D is a cross-sectional view schematically illustrating cutting alens blank to singulate lenses in a method of manufacturing a lensaccording to the third embodiment;

FIG. 12A is a plan view schematically showing a structure of a lensaccording to a fourth embodiment;

FIG. 12B is a schematic perspective cross-sectional view taken alongline XIIB-VIIB of FIG. 12A;

FIG. 13A is a plan view schematically showing a structure of a lensaccording to a fifth embodiment;

FIG. 13B is a schematic perspective cross-sectional view taken alongline XIIIB-VIIIB of FIG. 13A;

FIG. 14 is a plan view schematically showing a structure of a lensaccording to a sixth embodiment;

FIG. 15 is a cross-sectional view schematically showing a structure of alight emitting device according to a seventh embodiment, taken along aline passing through the center of the light emitting device;

FIG. 16 is a cross-sectional view schematically showing a structure of alight emitting device according to an eighth embodiment;

FIG. 17A is a schematic plan diagram showing a variational example of aflange part of a lens and illustrating an engaged state of the flangepart with an engaging part;

FIG. 17B is a schematic plan diagram showing another variational exampleof a flange part of a lens and illustrating an engaged state of theflange part with an engaging part; and

FIG. 17C is a schematic plan diagram showing a variational example of alens and illustrating an engaged state of the lens with an engagingpart.

DESCRIPTION OF THE EMBODIMENTS

In the following, certain embodiments will be described with referenceto the drawings. However, the embodiments shown below are exemplifylenses, light emitting devices for embodying the technical idea of thepresent invention, and the technical idea of the present invention isnot limited thereto. The sizes, materials, shapes and the relativepositions of the members described in the embodiments are given asexamples and not as a limitation to the scope of the invention unlessspecifically stated. The sizes and positional relationships of themembers in each of drawings are occasionally shown exaggerated for easeof explanation.

First Embodiment

FIG. 1 is a perspective sectional view schematically showing a structureof a light emitting device that includes a lens according to a firstembodiment, taken along a line passing through the center of the lightemitting device. FIG. 2 is a plan view schematically showing a structureof a lens according to the first embodiment. FIG. 3 is a cross-sectionalview, taken along line of FIG. 2 , schematically showing a structure ofa lens according to the first embodiment, in which the line is passingthrough the center of the lens. FIG. 4 is a cross-sectional viewschematically showing a structure of a light emitting device accordingto the first embodiment, taken along a line passing through the centerof the light emitting device.

The light emitting device 100 includes a light emitting element 51 and alens 51. The light emitting device 100 further includes a base 52 onwhich the light emitting element 51 is mounted.

Lens

Lens 1 will be described.

The lens 1 includes a cover part 2 and a light-shielding part 3.

The cover part 2 of the lens 1 includes a lens part 21 having one ormore lateral sides, a connection part 22 constituting one or morelateral side walls each extending downward from a respective one of theone or more lateral sides of the lens part 21, and a flange part 23extending outward from a lower-end portion of a corresponding one of thelateral side walls constituted by the connection part 22. The lens part21 and the connection part 22 are formed of a thermosetting first resinand continuous to one another. The light-shielding part 3 of the lens 1covers outer lateral surfaces of the lateral side walls constituted bythe connection part 22 (and an upper surface of the flange part) andformed of a thermosetting second resin having a greaterlight-absorptance or a greater light-reflectance than the thermosettingfirst resin. The lens 1 is, for example, used as a flash lens for acellular phone or the like.

Cover Part

The cover part 2 includes a lens part 21, a flange part 23, and aconnection part 22, which are formed of a thermosetting first resin andcontinuous to one another. In the cover part 2, the lens part 21 and theconnection part 22 define a recess 4 having an opening facing downward,the lens part defines a bottom surface of the recess, and the connectionpart defines lateral surfaces of the recess. The lateral surfaces of therecess defines the opening of the recess. The flange part 23 extendsoutward from a periphery of the opening of the recess 4.

The lens part 21 is a member through which light from the light emittingelement 51 can be emitted to the outside in parallel light, condensedlight, or diffused light. The lens part 21 includes a light emittingsurface 21 a where light emitted from the light emitting element 51enters, and a light emitting surface 21 b at an opposite side to thelight incidence surface 21 a where the incident light is refracted andis emitted to the outside.

The outer shape in a plan view of the lens part 21 can be selected fromvarious appropriate shapes, examples thereof include a polygonal shapesuch as a quadrangular shape, a hexagonal shape, and an octagonal shape,a circular shape and an elliptic shape. A center portion of the lenspart 21 serves as a lens preferably has a circular shape or an ellipticshape, where a circular shape is more preferable. The lens part 21 has amaximum thickness of, for example, in a range of 0.1 mm to 10 mm,preferably in a range of 0.5 mm to 5 mm.

For the lens part 21, a Fresnel lens, a total internal reflection (TIR)lens, or the like can be used, in which, a Fresnel lens is preferable.The Fresnel lens 21 may have either a single lens-center or a pluralityof lens-centers. When a plurality of Fresnel lenses 21 are employed, theFresnel lenses are arranged corresponding to the arrangement of thelight emitting element 51, such that an odd number of Fresnel lenses arepreferably arranged in a zigzag form, and an even number of Fresnellenses are preferably arranged in a square matrix form.

The Fresnel lens 21 includes a plurality of concentric circles of ridges21 c on the light incidence surface 21 a and on the light emittingsurface 21 b. When combined, the cross-sectional shapes of the pluralityof ridges 21 c form a curved surface of a single convex lens. Theplurality of ridges 21 c are preferably arranged in concentric circlesor concentric ellipsoids in a radial direction of the Fresnel lens 21.In the Fresnel lens 21, the base plane of the plurality of ridges 21 ccan be flat, or concave or convex.

Each of the ridges 21 c has a cross-sectional shape formed with astraight portion at the center-side and a segment of a curved surface ofa lens at the outer-side. The profile of each of the ridges 21 c may beformed with inwardly curved segment either a concave curve or a convexcurve, in conformity to the direction of light to be emitted. The angles(Fresnel angles) at the tips of the ridges 21 c are adjusted such thatlight from the light emitting element 51 is emitted to the outside inparallel light.

The connection part 22 constitutes lateral side walls each extendingdownward from a respective one of the lateral sides of the lens part 21such that an upper end portion of each side wall is contiguous to anupper end portion of the respective one of the lateral sides of the lenspart 21, that the side walls constituted by the connection part 22extend downward in a right angle with respect to the lens part 21, andthat a lower-end portion of the side walls of the connection part 22 iscontiguous to the flange part 23 in, for example, a right angle. Theconnection part 22 and the lens part 21 define the recess 4 having theopening facing downward to accommodate a light emitting element 51. In across-sectional view, the recess 4 is preferably of a rectangularU-shape, but a semicircular shape or a semi-elliptical shape can also beemployed. The connection part 22 is preferably formed such that the lenspart 21 is located at a center of a bottom surface of the recess 4. Thelens part 21 has a rectangular outer peripheral shape in a plan view andthe connection part 22 is disposed with respect to each side of therectangular shape, with the opposite sides of the connection part 22being in parallel to each other. The connection part 22 has a thicknesssmaller than a thickness of the flange part 23. When the connection part22 is formed with a thickness smaller than a thickness of the flangepart 23, the thickness of the connection part 22 can be, for example,preferably in a range of 30 μm to 100 μm, more preferably in a range of30 μm to 200 nm.

The flange part 23 is formed continuous to and protruding outward fromand perpendicular to a lower end portion of corresponding one of thelateral side walls constituted by the connection part 22. The flangepart 23 has a thickness greater than a thickness of the connection part22. The flange part 23 has a frame-like shape and formed along thelateral side walls of the connection part 22 such that the flange part23 entirely surrounds a lower-end portion of an outer periphery of thelateral side walls constituted by the connection part 22 as shown inFIGS. 1 and 2 , and is used for bonding or securing to a substrate 52 onwhich the light emitting element 51 is mounted. Incidentally, note thatthe flange part 23 may be constituted by one or more separate partsextending from and partially surrounding the lower-end portion of theouter periphery of the lateral side walls constituted by the connectionpart 22. That is, each of the one or more separate parts of the flangepart 23 may be formed at least along a portion of the lower-end portionof the outer periphery of the lateral side walls constituted by theconnection part 22.

More specifically, the flange part 23 has a thickness (D2) greater thana thickness (D1) of the connection part 22 (D1<D2) and also greater than30 μm. The flange part 23 has a thickness in a range greater than 30 μmto 1000 μm, preferably in a range of 50 to 1000 μm or, more preferablyin a range of 100 μm to 1000 μm, further preferably in a range greaterthan 200 μm to 1000 μm. Thus, the flange part 23 has a thickness greaterthan the thickness of the connection part 22, which allows for stableconnection of the lens 1 to an engaging part 54 (for example, shown inFIG. 7A).

The length of the flange part 23 protruding outward from the lower endportion of the lateral side walls constituted by the connection part 22is preferably in a range of 200 μm to 3000 μm, more preferably in arange of 200 μm to 1000 μm. With this arrangement, stable bonding orsecuring between the flange part 23 and the substrate 52 can beobtained. This arrangement can also facilitate bonding with thesubstrate 52, when applying an adhesive material on the flange part 23.

The thickness (D2) of the flange part 23 with respect to the thickness(D1) of the connection part 22 can be 1.1 times or greater, preferably1.2 times or greater, more preferably 1.5 times or greater, and 3 timesor less, preferably 2.5 times or less, more preferably 2 times or less.

The thermosetting first resin used to form the cover part 2 is alight-transmissive thermosetting resin. Examples of the thermosettingresin include phenol resin, urea resin, melamine resin, epoxy resin,silicone resin, and polyurethane resin, and silicone resin ispreferable. The use of a thermosetting resin that is more resistant tolight and heat than a conventionally used thermoplastic resin such aspolycarbonate resin can reduce degradation of the cover part 2, andfurther can reduce degradation with the lapse of time, in which lightand heat concentrate in portions discolored by degradation, wheredarkening of the cover part 2 progresses in an accelerative manner.Moreover, silicone resin exhibits high flowability when heated, whichallows molding of the flange part 23 with a greater thickness.

Light-Shielding Part

The light-shielding part 3 is applied to cover outer lateral surfaces 22a of the lateral side walls constituted by the connection part 22 and anupper surface 23 a of the flange part 23, and is formed of athermosetting second resin having a greater light-absorptance or agreater light-reflectance than the thermosetting first resin.

The light-shielding part 3 is formed in a shape corresponding to theshapes of the connection part 22 and the flange part 23, with asubstantially uniform thickness. More specifically, the light-shieldingpart 3 has a shape in cross section corresponding to the shapes of theouter lateral surface 22 a of the lateral side walls constituted by theconnection part 22 and the upper surface 23 a of the flange part 23,which is, for example, an L-shape. The thickness of the light-shieldingpart 3 that is a thickness in a direction normal to the correspondingone of the lateral side walls constituted by the connection part 22 ornormal to the flange part 23 is preferably in a range of 200 μm to 3,000μm, more preferably in a range of 250 μm to 2,000 μm. With thisarrangement, the outer lateral surfaces 22 a of the lateral side wallsconstituted by the connection part 22 and the upper surface 23 a of theflange part 23 can be reliably covered by the light-shielding part 3,such that leaking of light through the outer lateral surfaces 22 a ofthe lateral side walls constituted by the connection part 22 and theupper surface 23 a of the flange part 23 can be substantially prevented.The light-shielding part 3 is disposed on the outer lateral surfaces 22a of the lateral side walls constituted by the connection part 22 and onthe upper surface 23 a of the flange part 23 without using an adhesivematerial. Because an adhesive material is not used, degradation ordetachment of the adhesive material, and/or absorption of light by anadhesive material do not occur.

The thermosetting second resin used to form the light-shielding part 3is a thermosetting resin having a greater light-absorptance or a greaterlight-reflectance than the light-transmissive first resin. For thethermosetting second resin, a black colored resin or white colored resinof a light-transmissive thermosetting resin similar to that used as thethermosetting first resin, preferably a silicone resin, containing ablack color material such as carbon having a high light absorptance, ora white color material such as titanium oxide having a high lightreflectance can be used. With this, the connection part 22 formed of thelight-transmissive first resin can be covered by the light-shieldingpart 3 formed of the thermosetting second resin having a high lightabsorptance or a high light reflectance, such that when the lens 1 is inoperation, light from the light emitting element 51 is absorbed orreflected at the light-shielding part 3 and leaking of light in alateral sides of the lens 1, particularly, through the connection part22 can be reduced.

Light Emitting Device

Next, the light emitting device 100 will be described.

The light emitting device 100 includes a light emitting element 51, alens 1, and preferably a substrate 52. A lens part 21 of the lens 1 isarranged at a position such that light from the light emitting element51 can be transmitted through the lens part 21. The light emittingdevice 100 may further include a light-transmissive member 53. The lightemitting device 100 includes the lens 1 whose outer lateral surfaces arecovered by the light-shielding part 3, such that light from the lightemitting element 51 is absorbed or reflected by the light-shielding part3, and thus leaking of light in the lateral sides of the lens 1 can bereduced. The lens 1 is similar to that described above and therefore thedescription thereof will be appropriately omitted.

Light Emitting Element

The light emitting element 51 preferably include at least anitride-based semiconductor layered structure. The nitride-basedsemiconductor layered structure includes a first semiconductor layer(for example, an n-type semiconductor layer), a light emitting layer,and a second semiconductor layer (for example, a p-type semiconductorlayer) layered in this order, which configured to generate light. Thenitride-based semiconductor layered structure has a thickness ofpreferably 30 μm or less.

The first semiconductor layer, the light-emitting layer, and the secondsemiconductor layer can be respectively an appropriate type, made ofappropriate materials. Examples thereof include a Group III-V compoundsemiconductor and a Group II-VI compound semiconductor. More specificexamples include nitride-based semiconductor materials such asIn_(X)Al_(Y)Ga_(1-X-Y)N (0≤X, 0≤Y, X+Y≤1); for example, InN, AlN, GaN,InGaN, AlGaN, InGaAlN, or the like. For the thickness and structure ofeach of the layers, any appropriate thickness and structure known in theart can be employed. The light emitting element 51 generally has aquadrangular shape in a plan view, but can have any appropriate shapesuch as a circular shape, an elliptical shape, or a polygonal shape suchas a triangular shape, a quadrangular shape, or a hexagonal shape.

Light-Transmissive Member

It is preferable that an upper surface of the light emitting element 51is covered by a light-transmissive member 53 disposed by using aspraying method or the like. The light-transmissive member 53 isconfigured to protect the light emitting element 51 from an externalforce, dust, moisture, or the like, and also to improve heat-resistingproperties, weather resistant properties, and light-resisting propertiesof the light emitting element 51. It is preferable that the sealingmember can transmit 60% or greater light emitted from the light emittinglayer. Such a light-transmissive member 53 can be formed of athermosetting resin, a thermoplastic resin, a modified resin of such aresin, a hybrid resin which includes one or more of those resins, or thelike. More specifically, an epoxy/modified epoxy resin, asilicone/modified silicone/hybrid silicone resin, or the like can beused.

In order to adjust the color of emitted light, the light-transmissivemember 53 preferably contains a fluorescent material to convert thewavelength of light from the light emitting element 51. For thefluorescent material, a known material in the art can be used. Examplesof the fluorescent material include yttrium aluminum garnet (YAG)-basedfluorescent material activated with cerium.

The light-transmissive member 53 may contain a filler material (forexample, a diffusion agent, a coloring agent, or the like). Examples ofthe filler material include silica, titanium oxide, zirconium oxide,magnesium oxide, glass, a crystal or sintered body of a fluorescentmaterial, and a sintered body of a fluorescent material and an inorganicbinding material.

Substrate

The substrate 52 is configured to mount a light emitting element 51, andfor example, includes a base material made of such as sapphire, spinel,or SiC, and a wiring pattern formed on or/and in the base material.

The light emitting element 51 is preferably flip-chip mounted on thesubstrate 52. On the substrate 52, either a single or a plurality oflight emitting elements 51 can be mounted. When a plurality of lightemitting element 51 is mounted on the substrate 52, the light emittingelements 51 may be arranged irregularly, or arranged regularly such asin rows and columns, or periodically. The type of connection used inconnecting the plurality of light emitting elements 51 can be in series,in parallel, in series-parallel or in parallel-series.

Arrangement of Light Emitting Element and Lens

The lens 1 is disposed such that the lens part 21 is at a position thatallows light from the light emitting element 51 to be transmittedthrough the lens part 21. The lens 1 is disposed on the base 52 throughthe flange part 23, with the lens part 21 facing the light emittingelement 51. Accordingly, the lens 1 is disposed on the substrate 52 withthe lens part 21 facing the light emitting element 51, such that lightfrom the light emitting element 51 leaking through the flange part 23 inlateral sides of the lens 1 can be reduced.

The light emitting element 51 is arranged spaced apart from the lenspart 21 and the connection part 22. More specifically, a depth of therecess 4 defined by the lens part 21 and the lateral side wallsconstituted by the connection part 22 is in a range of about 0.4 mm to1.5 mm. Accordingly, a gap between the bottom surface of the recess 4and the upper surface of the light emitting element 51 is in a range ofabout 0.05 mm to 0.5 mm. With this arrangement, heat from the lightemitting element 51 can be prevented from directly conducted to the lenspart 21, and thermal degradation of the lens part 21 can be reduced.

In the lens 1, the connection part 22 is formed such that a distancefrom the lens part (Fresnel lens) 21 to the light emitting element 51 issmaller than a distance from the connection part 22 to the lightemitting element 51. In the lens 1, a recess 4 is defined by the lenspart (Fresnel lens) 21 and the connection part 22 such that a distancefrom the lens part (Fresnel lens) 21 to the light emitting element 51 issmaller than a distance from the connection part 22 to the lightemitting element 51. More specifically, the center of the light emittingelement 51 (or a geometrical center of the light emitting element 51) isfacing the center of the Fresnel lens 21 (or a geometrical center of theFresnel lens 21). In other words, the lens 1 is disposed such that thecenter of the ridges 21 c of the lens 1 arranged in concentric circlesor concentric ellipsoids and the center of the light emitting element 51are aligned. When the lens includes a plurality of lens parts 21, thatis, when the lens is a compound eye lens, the light emitting element 51may be arranged with a shift such that the center of the light emittingelement 51 is closer to the center of the entire lens. With thearrangements of the light emitting element 51 described above, a certaingap can be maintained between the light emitting element 51 and theconnection part 22 and between the light emitting element 51 and theflange part 23, such that light of the light emitting element 51 passingthrough the flange part 23 can be reduced.

The lens 1 has the flange part 23 with a thickness (D2) greater than athickness (D1) of the connection part 22 (D1<D2), which allows reliableconnection with an engaging part 54 (for example shown in FIG. 7A)provided at an outer side with respect to the designated disposinglocation of the lens 1.

Method of Manufacturing Lens

Next, a method of manufacturing a lens will be described. FIG. 5 is aflow chart showing a procedure of a method of manufacturing a lensaccording to the first embodiment. FIG. 6A is a cross-sectional viewschematically illustrating forming a cover blank in a method ofmanufacturing a lens according to the first embodiment. FIG. 6B is across-sectional view schematically showing removing a first mold in amethod of manufacturing a lens according to the first embodiment. FIG.6C is a cross-sectional view schematically illustrating arranging acover blank in a second mold and forming a lens blank in a method ofmanufacturing a lens according to the first embodiment. FIG. 6D is across-sectional view schematically illustrating cutting a lens blank toobtain individual lenses in a method of manufacturing a lens accordingto the first embodiment.

Although FIG. 6A to FIG. 6D illustrate manufacturing of a plurality oflenses, manufacturing of a single lens will be described below, andcorresponding description of manufacturing adjacent lenses will beappropriately omitted.

The method of manufacturing a lens 1 includes forming (S1) a coverblank, removing (S2) a first mold, arranging (S3) the cover blank in asecond mold, forming (S4) a lens blank, and obtaining (S5) individuallenses, which are performed in this order. Accordingly, the lens 1allowing for a reduction of leakage of light can be obtained. Formingthe cover blank 20 with a thickness (D1) of the connection part 22smaller than a thickness (D2) of the flange part 23, the lens 1 can bestably connected to an outer engaging part 54 (shown in FIG. 7A).

The description of material and arrangement etc., of each member are asin the lens 1 and therefore the description thereof will beappropriately omitted.

Forming Cover Blank

In forming (S1) a cover blank, a thermosetting first resin is injectedin a first mold and cured to form a cover blank 20 having a plurality ofcover parts 2 each having a lens part 21 having lateral sides, aconnection part 22 constituting lateral side walls each extendingdownward from a respective one of the lateral sides of the lens part 21,and a flange part 23 extending outward from a lower-end portion of thelateral side walls constituted by the connection part 22. The lens part21, the connection part 22, and the flange part 23 are formed continuouswith one another.

In the forming (S1) a cover blank, an upper mold 61 and a lower mold 62adapted for transfer molding are used as the first mold. The upper mold61 and the lower mold 62 are closed, the thermosetting first resin,which is heated and softened, is injected under pressure into the firstmold through a resin injecting port 61 a formed in the upper mold 61.The thermosetting first resin is cured in the heated mold, such that acover blank 20 having a plurality of cover parts 2 connected one anotherat the flange part 23 is molded.

In the forming (S1) a cover blank, the upper mold 61 and the lower mold62 are designed to produce a cover blank 20 having the plurality ofcover parts 2 each formed with a recess having an opening facingdownward, which is defined by the lens part 21 and the connection part22 and is located inward of the flange part 23. Further, in the forming(S1) a cover blank, the upper mold 61 and the lower mold 62 are designedto produce a cover blank 20 having a plurality of cover parts 2, arespective one of which has a lens part 21 having a plurality of ridges21 c on both sides, with the flange part 23 having a thickness (D2)greater than a thickness (D1) of the connection part 22, for example, athickness of the flange part 23 greater than 30 μm.

Removing First Mold

In the removing (S2) the first mold, a part or all parts of the firstmold is removed after the cover blank 20 is formed. In the firstembodiment, the upper mold 61 that is a part of the first mold isremoved and the cover blank 20 is held by the lower mold 62.

Arranging Cover Blank in Second Mold

In the arranging (S3) the cover blank in the second mold, another uppermold 71 which is also adapted for transfer molding is arranged on thelower mold 62 holding the cover blank 20. In the arranging (S3) thecover blank in the second mold, the upper mold 71 and the lower mold 62are used as the second mold.

Forming Lens Blank

In the forming (S4) a lens blank, a thermosetting second resin having agreater light-absorptance or a greater light-reflectance than thethermosetting first resin is injected in the second mold and cured, toform a lens blank 10 having a light-shielding part 3 between adjacentcover parts 2.

In the forming (S4) a lens blank, the upper mold 71 and the lower mold62 are closed, and the thermosetting second resin, which is heated andsoftened, is injected under pressure into the second mold through aresin injecting port 71 a formed in the upper mold 71. The thermosettingsecond resin is cured in the heated mold, such that a lens blank 10having a light-shielding part 3 between adjacent cover parts 2, in abent shape in a cross-section that is in conformity to the shapes of theouter lateral surfaces 22 a of the lateral side walls constituted by theconnection part 22 and the upper surface 23 a of the flange part 23 ismolded.

Obtaining individual Lenses

As shown in FIG. 6D, in the obtaining (S5) individual lenses, the lensblank 10 is singulated into individual lenses 1. That is, in theobtaining (S5) individual lenses, all parts of the second mold areremoved to take out the lens blank 10, and the lens blank 10 is cutalong a center of the light-shielding part 3 between adjacent coverparts 2. The singulating is performed by cutting at the light-shieldingpart 3, thus obtaining individual lenses 1 each having thelight-shielding part 3 covering the outer lateral surfaces of thelateral side walls constituted by the connection part 22 and the uppersurface 23 a of the flange part 23.

Further, in the obtaining (S5) individual lenses, a center of thelight-shielding part 3 between outer lateral surfaces 22 a of thelateral side walls constituted by two adjacent connection parts 22 ofthe lens blank 10 is cut together with the flange part 23 to obtain anindividual lens 1 having the outer lateral surfaces 22 a of the lateralside walls constituted by the connection part 22 and the upper surface23 a of each of the one or more flange parts 23 covered by thelight-shielding part 3. In a cross-section, the light-shielding part 3of each of the individual lenses 1 has a rectangular shape in conformityto the shapes of the outer lateral surfaces 22 a of the lateral sidewalls constituted by the connection part 22 and the upper surface 23 aof the flange part 23. Cutting of the light-shielding part 3 can beperformed by using a cutting tool 91 such as a blade or the like knownin the art. It is preferable to adjust the cutting width of the cuttingtool 91 such that the flange part 23 of the lens 1 has a length in arange of 200 μm to 1,000 μm.

Method of Manufacturing Light Emitting Device

Next, a method of producing a light emitting device 100 will bedescribed. Although the method of manufacturing the light emittingdevice 100 is not shown in the drawings, the method will be describedwith reference to FIG. 1 and FIG. 4 that show the structure of the lightemitting device 100.

The method of manufacturing the light emitting device 100 includesproviding a lens and disposing the lens with respect to the lightemitting element that has been positioned.

The providing a lens is similar to that described in the method ofmanufacturing a lens and therefore the description thereof will beappropriately omitted.

Disposing Lens

In the disposing a lens, the lens 1 is disposed such that light from thelight emitting element 51 to be transmitted through the lens part 21 ofthe lens 1. In the disposing a lens, the lens 1 is disposed such thatthe light emitting element 51, which is preferably has been mounted on asubstrate 52, is accommodated in the recess 4 having an opening facingdownward. The recess 4 is defined by the lens part 21 and the connectionpart 22. The lens part 21 defines a bottom surface of the recess 4 andthe connection part 22 defines lateral surface(s) of the recess 4. Thelateral surface(s) define the opening of the recess 4. The opening ofthe recess 4 is located inward of the flange part 23. The light emittingelement 51 may be covered by a light-transmissive member 53.

In the disposing a lens, it is preferable that the light emittingelement 51 is mounted on a substrate 52, in which the light emittingelement 51 is flip-chip mounted on the substrate 52 by using soldering.It is preferable that after the light emitting element 51 is mounted onthe substrate 52, the flange part 23 is connected to the substrate 52.In the disposing a lens, the lens 1 is disposed such that the connectionpart 22 and the lens part 21 of the lens 1 are spaced apart from thelight emitting element 51. More specifically, a gap between the bottomsurface of the recess 4 and the upper surface of the light-transmissivemember 51 or the upper surface of the light-transmissive member 53 ispreferably in a range of 0.05 mm to 0.5 mm. Further, in the disposing alens, the connection part 22 (recess 4) is preferably formed such that adistance from the lens part 21 to the light emitting element 51 issmaller than a distance from the connection part 22 to the lightemitting element 51. More specifically, the center of the light emittingelement 51 (or a geometrical center of the light emitting element 51) ispreferably aligned with the center of the lens part (the Fresnel lens)21 (or a geometrical center of the lens part (Fresnel lens) 21), thatis, aligned with the centers of the ridges 21 c arranged in concentriccircles or concentric ellipsoids.

When the lens 1 is disposed such that the light emitting element 51 isaccommodated in the recess 4, the lens 1 may be disposed via an engagingpart 54 as shown in FIG. 7A to FIG. 7C. FIG. 7A is a schematiccross-sectional diagram illustrating a state of arranging a lensaccording to the first embodiment via an engaging member with respect toa substrate having a light emitting element mounted thereon. FIG. 7B isa cross-sectional diagram illustrating a state of engaging a flange partof a lens according to the first embodiment with an engaging member.FIG. 7C is a schematic cross-sectional view illustrating a lens arrangedon a substrate, in which a flange part of a lens according to the firstembodiment is engaged with an engaging part. The substrate 52 may beprovided beforehand with the engaging part 54 at a predeterminedlocation around the light emitting element 51. The engaging part 54 hasan inwardly projecting end portion and a shaft portion, and the endportion has a thickness greater than that of a shaft portion. Theengaging part 54 is disposed such that a tip of the inwardly projectingend portion is at a location corresponding to substantially a half ofprotruding length of the flange part 23. Thus, together with thelight-shielding part 3, the flange part 23 can be engaged with theengaging part 54. Either the engaging part 54 or the flange part 23 ofthe lens 1 is elastically deformed (in FIG. 7B, the engaging part 54 iselastically deformed) to engage the flange part 23 (the flange part 23and the light-shielding part 3) with the engaging part 54. Thus, thelens 1 is disposed on the substrate 52. In the lens 1, the flange part23 has a thickness greater than a thickness of the connection part 22,which allows stable attachment to the engaging part 54.

Second Embodiment

Next, a second embodiment will be described with reference to FIG. 8A.

FIG. 8A is a cross-sectional view schematically showing a structure of alight emitting device that includes a lens according to a secondembodiment, taken along a line passing through the center of the lightemitting device. The same reference numerals may be applied to thecomponents that have been described above and description thereof may beappropriately omitted.

Lens and Light Emitting Device

A lens 1A and a light emitting device 100A will be described.

In the lens 1A and the light emitting device 100A according to thesecond embodiment, a light-shielding part 3A has a large thickness and arectangular cross-sectional shape which is in conformity to outerlateral surfaces 22 a of the lateral side walls constituted by theconnection part 22. This is different from the connection part 22 of thefirst embodiment, which has a cross-sectional shape bent along theshapes of the outer lateral surfaces 22 a of the lateral side wallsconstituted by the connection part 22 and the shape of the upper surface23 a of the flange part 23. Other structures are similar to the lens 1and the light emitting device 100 according to the first embodiment. Thelight-shielding part 3A is disposed with the same thickness as thelength of the flange part 23 extending outward from the connection part22. The outer lateral surface of the light-shielding part 3A and theouter end surface of the flange part 23 are flush with each other, whichcan reduce occurrence of detachment at the interface between thelight-shielding part 3A and the flange part 23. The light-shielding part3A preferably covers an entire outer lateral surfaces 22 a of thelateral side walls constituted by the connection part 22.

The lens 1A and the light emitting device 100A according to the secondembodiment have the light-shielding part 3A with a larger thickness asdescribed above, and thus leaking of light can be further reduced. Also,the flange part 23 has a larger thickness than that of the connectionpart 22, which together with the light-shielding part 3A, can enhancemechanical strength, such that when the cover part 2 is bonded to thesubstrate 52 via an adhesive material, stable bonding can be obtained.

Obtaining Individual Lenses

Next, a method of obtaining individual lenses 1A will be described.

FIG. 8A is a cross-sectional view schematically illustrating forming acover blank in a method of manufacturing a lens according to the secondembodiment. FIG. 8C is a cross-sectional view schematically illustratingcutting a lens blank into individual lenses in a method of manufacturinga lens according to the second embodiment.

The obtaining individual lenses 1A includes, similar to that in theobtaining individual lenses according to the first embodiment, forming(S1) a cover blank, removing (S2) a first mold, arranging (S3) the coverblank in a second mold, forming (S4) a lens blank, and obtaining (S5)individual lenses, which are performed in this order. The first mold andthe second mold are designed such that the flange part 23 has athickness greater than that of the connection part 22.

The obtaining individual lenses 1A is similar to the obtainingindividual lenses 1 according to the first embodiment except that, inthe arranging (S3) a cover blank 20 in the second mold, the cover blank20 is arranged in a second mold (an upper mold 81 and a lower mold 62)that is different from the second mold (the upper mold 71 and the lowermold 62) used in the first embodiment. In the forming (S4) a lens blank,a thermosetting second resin having a greater light-absorptance or agreater light-reflectance than the thermosetting first resin is injectedin the second mold and cured, to form a lens blank 10A having alight-shielding part 3A having a rectangular cross-sectional shape thatis in conformity to the outer lateral surfaces 22 a of the lateral sidewalls constituted by the connection part 22, between adjacent coverparts 2. The thermosetting second resin is injected from a resininjecting port 81Aa of the upper mold 81A. Further, in the obtainingindividual lenses 1A, a center of the light-shielding part 3A betweenouter lateral surfaces 22 a of the lateral side walls constituted by twoadjacent connection parts 22 of the lens blank 10A is cut together withthe flange part 23 to obtain individual lenses 1A each having the outerlateral surfaces 22 a of the lateral side walls constituted by theconnection part 22 and the upper surface 23 a of the flange part 23covered by the light-shielding part 3. In a cross-section, thelight-shielding part 3A of the individual lens 1A thus obtained has arectangular shape in conformity to the shape of the outer lateralsurface 22 a of the connection part 22.

Method of Manufacturing Light Emitting Device

Next, a method of manufacturing a light emitting device 100B will bedescribed.

The method of manufacturing the light emitting device 100B includesproviding a lens 1A and disposing the lens 1A which are performed inthis order. The method of manufacturing the light emitting device 100Bcan be performed in a similar manner as in the method of manufacturingthe light emitting device 100 according to the first embodiment, exceptfor using the lens 1B.

Third Embodiment

Next, a third embodiment will be described with reference to FIG. 9 .

FIG. 9 is a cross-sectional view schematically showing a structure of alight emitting device that includes a lens according to a thirdembodiment, taken along a line passing through the center of the lightemitting device. In the description below, the same reference numeralswill be applied to the structure of the flexible substrate member 1 anddescription thereof will be omitted.

Lens and Light Emitting Device

A lens 1B and a light emitting device 100B will be described. A flangepart 23 has a thickness greater than a thickness of a connection part22.

In the lens 1B and the light emitting device 100B according to the thirdembodiment, a light-shielding part 3B has a thickness greater than thethickness of the light-shielding part 3A of the second embodiment, andthe shielding part 3B also covers an outer end surface 23 b of theflange part 23. Others are similar to those of the method ofmanufacturing the lens 1A and the light emitting device 100A, accordingto the second embodiment.

The lens 1B and the light emitting device 100B according to the thirdembodiment have the light-shielding part 3B having a greater thicknessthat covers the outer lateral end surface 23 b of the flange part 23,thus yielding a further reduction of leaking light through thelight-shielding part 3B.

Method of Manufacturing Lens

Next, a method of manufacturing a light Lens 100B will be described.

FIG. 10 is a flow chart showing a procedure of a method of manufacturinga lens according to the first embodiment. FIG. 11A is a cross-sectionalview schematically illustrating forming a cover blank in a method ofmanufacturing a lens according to the third embodiment. FIG. 11B is across-sectional view schematically illustrating cutting a cover blank ina method of manufacturing a lens according to the third embodiment. FIG.11C is a cross-sectional view schematically illustrating arranging a cutcover blank in a second mold and forming a lens blank in a method ofmanufacturing a lens according to the third embodiment. FIG. 11D is across-sectional view schematically illustrating cutting a lens blank toobtain individual lenses in a method of manufacturing a lens accordingto the third embodiment.

The method of manufacturing a lens 1B includes forming (S11) a coverblank, removing (S12) a first mold, cutting (S13) the cover blank,arranging (S14) the cover blank in a second mold, forming (S15) a lensblank, and obtaining (S16) individual lenses, which are performed inthis order. With the method of manufacturing described above, a lens 1Byielding a reduction of leaking light can be produced.

The materials and arrangements of the members are similar to thosedescribed for the lens 1B and therefore the description thereof will beappropriately omitted.

Forming Cover Blank

As shown in FIG. 11A, in the forming (S11) a cover blank, athermosetting first resin is injected in a first mold and cured to forma cover blank 20 having a plurality of cover parts 2 each having a lenspart 21 having lateral sides, connection part 22 constituting lateralside walls each extending downward from a respective one of the lateralsides of the lens part 21, and a flange part 23 extending outward from alower-end portion of the lateral side walls constituted by theconnection part 22. The lens part 21, the connection part 22, and theflange part 23 are formed continuous with one another.

In the forming (S11) a cover blank, an upper mold 61 and a lower mold 62adapted for transfer molding are employed as the first mold. The uppermold 81A and the lower mold 82A are closed, and the thermosetting secondresin, which is heated and softened, is injected under pressure into thesecond mold through a resin injecting port 61 a provided in the uppermold 61. The thermosetting first resin is cured in the heated mold, suchthat a cover blank 20 having a plurality of cover parts 2 connected toone another at the flange parts 23 is molded.

In the forming (S11) a cover blank, the upper mold 61 and the lower mold62 are designed to produce a cover blank 20 having a plurality of coverparts 2 each formed with a recess having an opening facing downward. Therecess is defined by the lens part 21 and the connection part 22 with anopening located inward of the flange part 23. Each of the lens parts 21of the cover blank 20 has a plurality of ridges 21 c at both upper andlower sides. Further, in the forming (S11) a cover blank, the upper mold61 and the lower mold 62 are designed to produce a cover blank 20 havinga plurality of cover parts 2 each having the flange part 23 with athickness greater than 30 μm, which is greater than a thickness of theconnection part 22.

Removing First Mold

In the removing (S12) the first mold, the first mold is removed afterthe cover blank 20 is formed. In this step, all parts (the upper mold 61and the lower mold 62) of the first mold are removed.

Cutting Cover Blank

As shown in FIG. 11B, in the cutting (S13) the cover blank, the coverblank 20 is cut at the flange part 23 between adjacent cover parts 2 toobtain individual cover blanks 20A. Cutting of the cover blank 20 can beperformed by using a cutting tool 91 such as a known blade or the like.It is preferable to adjust the cutting width of the cutting tool 91 suchthat the flange part 23 of the individual cover blank 20A has a lengthin a range of 200 μm to 1000 μm.

Arranging Cover Blank in Second Mold

In the arranging (S14) the cover blank in the second mold, cut coverblank 20 (singulated cover blank 20A) is arranged in another set of mold(an upper mold 81A and a lower mold 82A) adapted for transfer molding.

Forming Lens Blank

In the forming (S15) a lens blank, a thermosetting second resin having agreater light-absorptance or a greater light-reflectance than thethermosetting first resin is injected in the second mold and cured, toform a lens blank 10B having a light-shielding part 3 between adjacentcover parts 2. In the forming (S15) a lens blank, the upper mold 81A andthe lower mold 82A are closed, and the thermosetting second resin, whichis heated and softened, is injected under pressure into the second moldthrough a resin injecting port 81Aa formed in the upper mold 81A. Thethermosetting second resin is cured in the heated mold, such that a lensblank 10B having a light-shielding part 3B between adjacent cover parts2, in a rectangular shape in a cross-section that is in conformity tothe shape of the outer lateral surface 22 a of the side wallsconstituted by the connection part 22 and covering an upper surface 23 aand an outer end surface 23 b of the flange part 23 is molded.

Obtaining Individual Lenses

As shown in FIG. 11D, in the obtaining (S16) individual lenses, the lensblank 10B is singulated into individual lenses 1B. That is, in theobtaining (S16) individual lenses, all parts of the second mold areremoved to take out the lens blank 10B, and the lens blank 10B is cutalong a center of the light-shielding part 3B between adjacent coverparts 2. The singulating is performed by cutting at the light-shieldingpart 3B, thus obtaining individual lenses 1B each having thelight-shielding part 3B covering the outer lateral surfaces 22 a of thelateral side walls constituted by the connection part 22 and alsocovering the outer end surfaces 23 b of the flange part 23.

In the obtaining (S16) individual lenses, the lens blank 10B is cutalong the center of the light-shielding part 3B between the outerlateral surfaces 22 a of the lateral side walls constituted by theconnection part 22 and between outer end surfaces 23 b of adjacentflange parts 23 of the lens blank, to obtain individual lenses 1B eachhaving the light-shielding part 3 covering the outer lateral surfaces 22a of the lateral side walls constituted by the connection part 22, theupper surface 23 a of the flange part 23, and the outer end surfaces ofthe flange part 23. In a cross-section, the light-shielding part 3B ofeach of the individual lenses 1B has a rectangular shape in conformityto the shapes of the outer lateral surfaces 22 a of the lateral sidewalls constituted by the connection part 22 and covering the outer endsurface 23 b of the flange part 23. Cutting of the light-shielding part3B can be performed by using a cutting tool 91 such as a known blade orthe like.

Method of Manufacturing Light Emitting Device

Next, a method of manufacturing a light emitting device 100B will bedescribed.

The method of manufacturing the light emitting device 100B includesproviding a lens and disposing the lens, which can be performed in thisorder. The method of manufacturing the light emitting device 100B can beperformed in a similar manner as in the method of manufacturing thelight emitting device 100 according to the first embodiment, except forusing the lens 1B.

Fourth Embodiment, Fifth Embodiment

In the first embodiment to the third embodiment, structures includingthe flange part 23 provided along a lower end-portion (e.g., anopening-end portion) of entire outer periphery of the lateral side wallsconstituted by the connection part 22 have been illustrated, but asshown in FIG. 12A, FIG. 12B, FIG. 13A, and FIG. 13B, one or more flangeparts 23 d may be formed such that each flange part 23 d is formedextending outward from a lower end portion of a corresponding one of thelateral side walls constituted by the connection part 22. FIG. 12A is aplan view schematically showing a structure of a lens according to afourth embodiment. FIG. 12B is a schematic cross-sectional view takenalong line XIIB-VIIB of FIG. 12A. FIG. 13A is a plan view schematicallyshowing a structure of a lens according to a fifth embodiment. FIG. 13Bis a schematic cross-sectional view taken along line XIIIB-XIIIB of FIG.13A.

As shown in FIG. 12A and FIG. 12B, in the lens 1D and the light emittingdevice 100D according to the fourth embodiment, each flange part 23 d isformed extending outward from a lower end portion of a corresponding oneof the outer lateral surfaces of the lateral side walls of theconnection part 22 along a partial length thereof. With this structure,the volume of the flange part 23 d can be reduced. That is, the surfacearea of the flange part 23 d can be reduced. Further, the lens 1Dincludes a light-shielding part 3 d covering an upper surface andlateral end surfaces of each flange part 23 d and the lateral outersurfaces of the lateral side walls constituted by the connection part22. Accordingly, when the lens 1D is in operation, leaking of lightthrough lateral sides of the lens 1D, particularly leaking of lightthrough the flange parts 23 d can be further reduced.

The flange parts 23 d are formed at locations such that, in a plan view,each two opposite flange parts 23 d are substantially symmetric about aplane parallel to their corresponding ones of the lateral side wallsconstituted by the connection part 22 and is passing through the centerof the lens part 21. The flange parts 23 d have a thickness greater thanthat of the connection part 22. The flange parts 23 d are arranged oneon the lower end portion of each of the outer lateral surfaces of thelateral side walls of the connection part 22, such that four flangeparts 23 d are arranged on the outer periphery of the connection part 22each along a partial length thereof. Each of the flange parts 23 d islocated substantially central to the width of the outer lateral surfaceof the corresponding one of the side walls constituted by the connectingpart 22. The flange parts 23 d each preferably have a width in a rangeof 50 μm to 1,000 μm. The flange parts 23 d each have a thickness ofpreferably 30 μm or greater, more preferably 50 μm, or 100 μm.

With the structure as described above, more stable bonding or fixing tothe substrate 52 can be achieved in the lens 1D and the light emittingdevice 100D according to the fourth embodiment.

As shown in FIG. 13A and FIG. 13B, in a lens 1E and a light emittingdevice 100E according to a fifth embodiment, two flange parts 23 e areformed on a lower end portion of each of the outer lateral surfaces ofthe lateral side walls constituted by the connection part 22, such thateight flange parts 23 e are arranged on the outer periphery of theconnection part 22 each along a partial length thereof. The flange parts23 e formed on the outer lateral surface of a single lateral side wallare spaced apart from each other. Each two spaced apart flange parts 23e formed on one outer lateral surface of the connection part 22 and thetwo spaced apart flange parts 23 e formed on the outer lateral surfaceopposite the one outer lateral surface are respectively located oppositefrom each other. Other structures are similar to that in the lens 1 andthe light emitting device 100 according to the first embodiment.

In the fifth embodiment, two flange parts 23 e are disposed on each ofthe outer lateral surfaces of the lateral side walls constituted by theconnection part 22, but three or four flange parts 23 e may be formed oneach of the outer lateral surfaces of the lateral side walls constitutedby the connection part 22. Different pair of opposite outer lateralsurfaces of the connection part 22 may be provided with a differentnumber of the flange parts 23 e.

Sixth Embodiment

For example, as the lens 1F and the light emitting device 100F shown inFIG. 14 , a lens part 21 f may be a compound eye lens having a pluralityof Fresnel lenses. FIG. 14 is a plan view schematically showing astructure of a lens 1F according to a sixth embodiment. The lens 1F hasa lens part 21 f including a circular lens functioning part at a centerof a rectangular shape in a plan view, and a flat plate-like shapearound surrounding the lens functioning parts. The circular lens part inthe lens part 21 f is cut in four, and a respective one of a quarter ofthe circular part is formed into a Fresnel lens. It is preferable thatlight emitting elements 51 of a number corresponding to the number ofthe Fresnel lens are disposed such that a center of each of the lightemitting elements 51 is offset toward the center of the lens part 21 ffrom the center of corresponding Fresnel lens of the lens part 21 f.When the lens part 21 f has a compound eye lens, disposing the lightemitting elements 51 with the centers offset from the centers of therespective Fresnel lenses as described above allows for an increase ofthe light extraction efficiency. It is further preferable that two typesof the light emitting elements 51 to emit two different emission colorsare employed and the light emitting elements 51 of the same emissioncolor are disposed diagonally. The lens 1F has a structure similar tothat shown in FIG. 1 , except that the flange part 23 f has a thicknessgreater than that of the connection part 22. The flange part 23 f may beprovided partially along the outer lateral surfaces of the side wallsconstituted by the connection part 22 as in the other embodiments.

Seventh Embodiment

As shown in FIG. 15 , a plano-convex Fresnel lens having a plurality ofridges 21 c on either upward-facing surface or downward-facing surface(in FIG. 15 , the light-incident surface 21 a) may be used in the lenspart 21 g of the lens 1G and the light emitting device 100G. FIG. 15 isa cross-sectional view schematically showing a structure of the lightemitting device according to a seventh embodiment. When a compound eyelens is employed, a structure having the plurality of projections 21 ceither in the upward-facing surface or the downward-facing surface ofthe lens part 21 g can also be employed. That is, it is preferable thatthe lens part 21 g has a light incident surface 21 a with a plurality ofridges 21 c, and a flat or substantially flat light-emitting surface 21b such that the light-emitting surface 21 b of the lens part 21 g can bearranged in parallel to the light emitting surface of the light emittingelement 51. The light-emitting surface 21 b may have microscopicprojections formed by emboss processing, mat processing, or the like,which are lower than the ridges 21 c. With this, light emitted throughthe light-emitting surface 21 b can be uniformly dispersed. As in thelens 1G and the light emitting device 100G, employing a structure havinga plurality of ridges 21 c only on the light-incident surface 21 a,allows for a reduction in a dimension in height direction, because theupward-facing surface does not have the ridges 21 c.

Eighth Embodiment

As shown in FIG. 16 , a lens 1H and a light emitting device 100H mayhave a structure in which a connection part 22 h is located only alongon a lateral side of the lens part 21 and a flange part 23 h is formedextending downward from the connection part 22 with a thickness greaterthan the thickness of the connection part 22 h. FIG. 16 is across-sectional view schematically showing a structure of the lightemitting device according to an eighth embodiment.

In the lens 1H, outer lateral surfaces of the connection part 22 andupper surfaces and outer lateral sides of the flange part 23 h arecovered by a light-shielding part 3 h. In the lens 1H, the flange part23 h and the lens part 21 h define a recess 4 h. In the lens 1H, thelower surface of the flange part 23 and the lower surface of thelight-shielding part 3 h are bonded to the substrate 52 through anadhesive such that the lens part 21 h faces the light emitting element51 mounted on the substrate 52. In the lens 1H, the flange part 23 h hasa thickness greater than that of the connection part 22 h, for example,the flange part 23 h has a thickness in a range of 30 μm to 1,000 μm.

In the light emitting device 100H, the light emitting element 51 mountedon the substrate 52 is spaced apart from the lens part 21 h of the lens1H depending on the height of the flange part 23 h of the lens 1H.

Variant Example

As shown in FIG. 17A and FIG. 17B, the lens and the light emittingdevice may include the flange part at different position(s) or indifferent numbers and/or shape(s) than those described above.Alternatively, as shown in FIG. 17C, the lens part and the connectionpart may have a shape other than a quadrangular shape in a plan view.FIG. 17A is a schematic plan diagram illustrating a variant example of aflange part of a lens and illustrating an engaged state of the flangepart with an engaging part. FIG. 17B is a schematic plan diagramillustrating another variant example of a flange part of a lens andillustrating an engaged state of the flange part with an engaging part.FIG. 17C is a schematic plan diagram illustrating a variant example of alens and illustrating an engaged state of the lens with an engagingpart.

As shown in FIG. 17A, the lens 101A may have four flange parts 123 a onfour sides of the connection part respectively, with a width equivalentto the width of the connection part. Alternatively, as shown in FIG.17B, the lens 101A may have two flange parts 123 b on opposite two sidesof the connection part respectively, with a width smaller than the widthof the connection part. The flange parts 123 a and the flange parts 123b may be respectively configured for slide engagement with engagingparts 154A and engaging parts 154B provided on the substrate, in therespective light emitting devices.

As shown in FIG. 17C, the lens 101C can be formed with the lens part 121c in a circular shape in a plan view, the connection part 122 c in acylindrical shape, and four flange parts 123 c provided every 90 degreeswith respect to the outer periphery of the connection part 122 c in aplan view, such that respective two flange parts 123 c are opposite toeach other. The outer lateral sides of the connection part 122 c and theupper surface and lateral end surfaces of each of the flange parts 123 care covered by the light-shielding part 103 c. As illustrated above, thelens part 121 c can be formed in a shape other than a quadrangular shapeand the connection part 122 c can be disposed in conformity with theshape of the lens part 121 c, at the outer edge of the lens part 121 cand downward. The light emitting device can be assembled by rotativelysliding the lens 101C such that the flange parts 123 c are engaged withrespective engaging parts 154C provided on the substrate. In the variantexample illustrated in FIG. 17C, the lens part 121 c has a circularshape, but the lens part 121 c can be in a triangular shape or apentagonal or higher polygonal shape. In each variational example, thelocation of the light-shielding part may be, as has been describedabove. The lens and light emitting device of each variational examplecan be manufactured according to the methods described above, withappropriately changing respective molds.

The lens and light emitting device, and the method of manufacturing thelens and the method of manufacturing the light emitting device describedabove are not limited to those embodiments described above.

It is to be understood that although the present invention has beendescribed with regard to preferred embodiments thereof, various otherembodiments and variants may occur to those skilled in the art, whichare within the scope and spirit of the invention, and such otherembodiments and variants are intended to be covered by the followingclaims.

What is claimed is:
 1. A lens comprising a cover part and alight-shielding part, wherein the cover part comprises: a lens parthaving one or more lateral sides; a connection part constituting one ormore lateral side walls each extending downward from a respective one ofthe one or more lateral sides of the lens part; and one or more flangeparts each extending outward from a lower-end portion of a correspondingone of the one or more lateral side walls, the lens part and theconnection part define a recess having an opening facing downward, thelens part defines a bottom surface of the recess, the one or morelateral side walls extend from the bottom surface of the recess anddefine lateral surfaces of the recess, which define the opening of therecess, the one or more flange parts extend outward from a periphery ofthe opening of the recess, the lens part, the one or more flange parts,and the connection part are formed of a thermosetting first resin andcontinuous to one another; the light-shielding part covers an entiretyof outer lateral surfaces of the one or more lateral side walls and anentirety of upper surfaces of the one or more flange parts and is formedof a thermosetting second resin having a greater light-absorptance or agreater light-reflectance than the thermosetting first resin; and theflange part has a greater thickness than the connection part.
 2. Thelens according to claim 1, wherein at least either the thermosettingfirst resin or the thermosetting second resin is silicone resin.
 3. Thelens according to claim 1, wherein the lens part is a Fresnel lens. 4.The lens according to claim 3, wherein the Fresnel lens is a compoundeye Fresnel lens having a plurality of lens centers.
 5. The lensaccording to claim 1, wherein the one or more flange parts have a lengthin a range of 200 μm to 3,000 μm.
 6. The lens according to claim 1,wherein the light-shielding part has a thickness in a range of 200 μm to3,000 μm.
 7. The lens according to claim 1, wherein the one or moreflange parts comprise a single flange part entirely surrounding the oneor more lateral side walls.
 8. The lens according to claim 1, whereinthe one or more flange parts comprise a plurality of flange parts, andthe plurality of flange parts are each formed extending from a lower-endportion of a corresponding one of the one or more lateral side walls ina manner partially surrounding the corresponding one of the one or morelateral side walls.
 9. The lens according to claim 8, wherein theplurality of flange parts each have a width in a range of 50 μm to 1,000μm.
 10. The lens according to claim 8, wherein two of the plurality offlange parts are located opposite to each other.
 11. The lens accordingto claim 1, wherein the light-shielding part is disposed on the entiretyof the outer lateral surfaces of the one or more lateral side walls andthe entirety of the upper surfaces of the one or more flange partswithout using an adhesive material.
 12. A lens comprising a cover partand a light-shielding part, wherein the cover part comprises: a lenspart having one or more lateral sides; a connection part constitutingone or more lateral side walls each extending downward from a respectiveone of the one or more lateral sides of the lens part; and one or moreflange parts each extending outward from a lower-end portion of acorresponding one of the one or more lateral side walls, the lens partand the connection part define a recess having an opening facingdownward, the lens part defines a bottom surface of the recess, the oneor more lateral side walls extend from the bottom surface of the recessand define lateral surfaces of the recess, which define the opening ofthe recess, the lens part, the one or more flange parts, and theconnection part are formed of a thermosetting first resin and arecontinuous to one another, the one or more flange parts each have athickness greater than 30 μm, and the light-shielding part covers anentirety of outer lateral surfaces of the one or more lateral side wallsand an entirety of upper surfaces of the one or more flange parts and isformed of a thermosetting second resin having a greaterlight-absorptance or a greater light-reflectance than the thermosettingfirst resin.
 13. The lens according to claim 12, wherein the recess islocated inward of the one or more flange part.
 14. The lens according toclaim 12, wherein the light-shielding part is disposed on the entiretyof the outer lateral surfaces of the one or more lateral side walls andthe entirety of the upper surfaces of the one or more flange partswithout using an adhesive material.
 15. A light emitting devicecomprising: a light emitting element; and a lens comprising a cover partand a light-shielding part, wherein the cover part comprises: a lenspart having one or more lateral sides; a connection part constitutingone or more lateral side walls each extending downward from a respectiveone of the one or more lateral sides of the lens part; and one or moreflange parts each extending outward from a lower-end portion of acorresponding one of the one or more lateral side walls; the lens partand the connection part define a recess having an opening facingdownward, the lens part defines a bottom surface of the recess, the oneor more lateral side walls extend from the bottom surface of the recessand define lateral surfaces of the recess, which define the opening ofthe recess, the one or more flange parts extend outward from a peripheryof the opening of the recess, the lens part, the one or more flangeparts, and the connection part are formed of a thermosetting first resinand are continuous to one another, the light-shielding part covers anentirety of outer lateral surfaces of the one or more lateral side wallsand an entirety of upper surfaces of the one or more flange parts and isformed of a thermosetting second resin having a greaterlight-absorptance or a greater light-reflectance than the thermosettingfirst resin, the one or more flange parts have a greater thickness thanthe connection part, and the lens part is disposed at a locationallowing light from the light emitting element to be transmitted throughthe lens part.
 16. The light emitting device according to claim 15,further comprising a substrate having the light emitting element mountedthereon, wherein the lens is disposed on the substrate with the one ormore flange parts connected to the substrate such that the lens partfaces the light emitting element.
 17. The light emitting deviceaccording to claim 15, wherein the light emitting element is spacedapart from the lens part and the connection part.
 18. The light emittingdevice according to claim 17, wherein the connection part is formed suchthat a distance between the lens part and the light emitting element issmaller than a distance between the connection part and the lightemitting element.
 19. The light emitting device according to claim 15,wherein the light-shielding part is disposed on the entirety of theouter lateral surfaces of the one or more lateral side walls and theentirety of the upper surfaces of the one or more flange parts withoutusing an adhesive material.
 20. A light emitting device comprising: alight emitting element; and a lens comprising a cover part and alight-shielding part, wherein the cover part comprises: a lens parthaving one or more lateral sides; a connection part constituting one ormore lateral side walls each extending from a respective one of the oneor more lateral sides of the lens part; and one or more flange partseach extending outward from a lower-end portion of a corresponding oneof the one or more lateral side walls, the lens part and the connectionpart define a recess having an opening facing downward, the lens partdefines a bottom surface of the recess, the one or more lateral sidewalls extend from the bottom surface of the recess and define lateralsurfaces of the recess, which define the opening of the recess, the lenspart, the one or more flange parts, and the connection part are formedof a thermosetting first resin and are continuous to one another, with athickness of each of the one or more flange parts being greater than 30μm, the light-shielding part covers an entirety of outer lateralsurfaces of the one or more lateral side walls and an entirety of uppersurfaces of the one or more flange parts and is formed of athermosetting second resin having a greater light-absorptance or agreater light-reflectance than the thermosetting first resin, and thelens part is disposed at a location allowing light from the lightemitting element to be transmitted through the lens part.
 21. The lightemitting device according to claim 20, wherein the light-shielding partis disposed on the entirety of the outer lateral surfaces of the one ormore lateral side walls and the entirety of the upper surfaces of theone or more flange parts without using an adhesive material.